1、Designation:D298896(Reapproved 2020)Standard Test Methods forWater-Soluble Halide Ion in Halogenated Organic Solventsand Their Admixtures1This standard is issued under the fixed designation D2988;the number immediately following the designation indicates the year oforiginal adoption or,in the case o
2、f revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 Test Methods 1,
3、2,and 3These test methods cover thedetermination of water-extractable halide ion in halogenatedorganic solvents and their admixtures.Fluoride ion is notmeasured due to the solubility of silver fluoride.1.2 Test Method 4This test method covers the determina-tion of chloride ion in halogenated organic
4、 solvents and theiradmixtures.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this
5、standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.Specific precautionary statements are given in Section 6.1.5 This international standard was developed in accor-dance with internationally recognized p
6、rinciples on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Summary of Test Method2.1 Summary of Test Methods 1,2,3Halide ion presen
7、t inhalogenated organic solvents is extracted with water andprecipitated as the silver halide salt with silver nitrate.Quantityof the halide present is determined by comparing the turbidityof the sample to known standards.The distilled water,as wellas all glassware used,must be halide-free.2.2 Summa
8、ry of Test Method 4This test method is basedon the determination of ionizable chloride by titration withmercuric acetate solution using s-diphenylcarbazone as theindicator.3.Significance and Use3.1 These test methods are used to establish manufacturingand purchasing specifications.These test methods
9、 will providea means of determining the condition of the solvent in use.Ahigh water soluble chloride level may indicate the start ofsolvent decomposition.4.Apparatus4.1 Separatory Funnel,500 mL,4.2 Nessler Tubes,50 mL,4.3 Erlenmeyer Flask,125 mL,and4.4 Colorimeter or Turbidimeter,Method 2.5.Reagents
10、5.1 Purity of ReagentsReagent grade chemicals shall beused in all test.Unless otherwise indicated it is intended that allreagents shall conform to the specifications of the Committeeon Analytical Reagents of the American Chemical Society,where such specification are available.2Other grades may beuse
11、d,provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.5.2 Purity of WaterUnless otherwise indicated,referencesto water shall be understood to mean halide-free distilled water.5.3 Chloride Standard(1 mL 0
12、.0001 g Cl),Test Methods1,2,and 3Prepare by adding 0.165 g of sodium chloride(NaCl)to 1 L of halide-free distilled water.1These test methods are under the jurisdiction of ASTM Committee D26 onHalogenated Organic Solvents and Fire Extinguishing Agents and are the directresponsibility of Subcommittee
13、D26.04 on Test Methods.Current edition approved April 1,2020.Published April 2020.Originallyapproved in 1971.Last previous edition approved in 2015 as D298896(2015).DOI:10.1520/D298896R20.2Reagent Chemicals,American Chemical Society Specifications,AmericanChemical Society,Washington,DC.For suggestio
14、ns on the testing of reagents notlisted by the American Chemical Society,see Analar Standards for LaboratoryChemicals,BDH Ltd.,Poole,Dorset,U.K.,and the United States Pharmacopeiaand National Formulary,U.S.Pharmacopeial Convention,Inc.(USPC),Rockville,MD.Copyright ASTM International,100 Barr Harbor
15、Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issu
16、ed by the World Trade Organization Technical Barriers to Trade(TBT)Committee.5.4 Chloride Standard(1 mL=0.000001 g Cl),TestMethod 4Dissolve 0.0660 g of sodium chloride in water anddilute to 1000 mL.Pipet 25 mL of this solution into a 1000 mLvolumetric flask,dilute to volume,and mix.5.5 Nitric Acid(sg gr 1.42),concentrated nitric acid(HNO3).5.6 Silver Nitrate Solution 0.1 NPrepare a 0.1 N solutionof silver nitrate(AgNO3).5.6.1 Prepare the silver nitrate solution by adding 16.99 g ofsilver nitrate
